CN-122014390-A - Exhaust gas purifying device

Abstract

An exhaust gas purifying device comprises a convex portion which is formed by projecting a strip-shaped sheet portion divided by a cutting portion of a front and rear portion in the longitudinal direction of a metal plate to the front side of the metal plate to form a gas flow path, and a concave portion which is formed by recessing another strip-shaped sheet portion divided by a cutting portion of another front and rear portion to the rear side to form a gas flow path, wherein the portions divided by the cutting portion are through holes, and wherein the convex portion and the concave portion are alternately formed in a side-by-side state in at least one of the longitudinal direction and the transverse direction via a flat plate-shaped predetermined connecting portion, and a plurality of metal plates including the convex portion and the concave portion on the front side and the rear side are laminated so that the convex portion and the concave portion are mutually displaced in the transverse direction, and the metal plates adjacent in the laminating direction are joined by at least the connecting portion.

Inventors

• UEDA TAKAHITO
• Ono Sasaki Haoyun

Assignees

• 丰田自动车株式会社

Dates

Publication Date

20260512

Application Date

20251023

Priority Date

20241112

Claims (5)

1. 1. An exhaust gas purification device for purifying exhaust gas generated by combustion by circulating the exhaust gas along a metal plate as a catalyst-supporting base material, characterized in that, The exhaust gas treatment device comprises a convex part, a strip-shaped sheet part and a concave part, wherein the strip-shaped sheet part is divided by a cutting part of the front and rear parts in the exhaust gas flowing direction, namely, the longitudinal direction, of the metal plate and is bent or curved to form a protruding gas flow path to one surface, namely, the surface side of the metal plate, and the concave part is divided by a cutting part of the other front and rear parts in the exhaust gas flowing direction, namely, the longitudinal direction, of the metal plate and is bent or curved to form a concave gas flow path to the other surface, namely, the back side of the metal plate, and The portion divided by the cutting portion becomes a through hole, The convex portions and the concave portions are alternately formed in a side-by-side state with a predetermined flat plate-like connecting portion interposed therebetween in at least one of the longitudinal direction and the transverse direction orthogonal to the longitudinal direction, The plurality of metal plates including the convex portions and the concave portions on the front surface side and the back surface side are stacked so that the convex portions and the concave portions are displaced from each other in the lateral direction, And the metal plates adjacent to each other in the stacking direction are joined by at least the flat plate-shaped connecting portions.
2. 2. The exhaust gas purifying apparatus according to claim 1, wherein, The top surface of the protruding part is connected with the flat plate-shaped connecting part of the other metal plates positioned at the upper side in the stacking direction, and The bottom surface of the recess is joined to the flat plate-shaped connecting portion of the other metal plate located on the lower side in the stacking direction.
3. 3. The exhaust gas purifying apparatus according to claim 1 or 2, characterized in that, In the metal sheet, The convex portions and the concave portions are alternately arranged side by side in the lateral direction, and Alternately arranged in the longitudinal direction and staggered from each other in the transverse direction.
4. 4. The exhaust gas purifying apparatus according to claim 1 or 2, characterized in that, In the metal sheet, The protrusions are arranged in a plurality of rows in the lateral direction, The concave portions are arranged in the lateral direction between the rows of the convex portions.
5. 5. The exhaust gas purifying apparatus according to claim 1 or 2, characterized in that, The length of the connecting part in the longitudinal direction is a prescribed length with the length Le determined by the following formula as the upper limit, and The length of the protruding portion and the recessed portion in the longitudinal direction is a predetermined length having a half length Le defined by the following formula as an upper limit, Le={dH/9.28×√(ρ·u/μ)} 2 DH: hydraulic diameter (m), ρ: gas density (kg/m 3 ), u: gas flow rate (m/s), μ: gas viscosity (Pas).

Description

Exhaust gas purifying device Technical Field The present invention relates to an apparatus for purifying exhaust gas by supporting a catalyst on a substrate and circulating the exhaust gas along the substrate, and more particularly, to a structure of a catalyst-supporting substrate. Background Exhaust gas generated in an internal combustion engine of a vehicle contains pollutants such as carbon monoxide (CO) and Hydrocarbons (HC). A catalytic converter that oxidizes or reduces these pollutants to render them harmless is incorporated into the exhaust system of an internal combustion engine. In order to purify exhaust gas using a catalyst, it is necessary to positively contact the exhaust gas with the catalyst, and various structures have been proposed in the past for this purpose. Japanese patent laid-open No. 11-290699 discloses a honeycomb catalyst for flue gas denitration. The honeycomb catalyst is mainly composed of a catalyst-supporting honeycomb structure, and a plurality of cells formed in the honeycomb structure serve as gas flow paths. If the gas flow path is long, a boundary film grows along the inner surface of the hole, and the diffusion resistance of exhaust gas to the catalyst increases. Therefore, in the honeycomb catalyst described in Japanese patent application laid-open No. 11-290699, a plurality of cut portions having a mutual spacing of 300mm or less are provided so as to flow laterally through the gas flow path. Further, japanese patent laying-open No. 2007-511699 discloses an exhaust gas purifying converter for an internal combustion engine using a panel composed of catalyst-supporting metal fibers. In the exhaust gas purifying converter disclosed in japanese patent laying-open No. 2007-511699, a metal plate is sandwiched between panels to be provided as one stack, and a plurality of stacks are stacked to be accommodated in a case. In each stack, the exhaust gas flows between the panels, and the exhaust gas flows through the panels, whereby the exhaust gas contacts the catalyst to purify the exhaust gas. In order to ensure the flow path of the exhaust gas, the metal plate is provided with a wing portion protruding toward one surface side thereof. The wing portions are, for example, bending pieces obtained by cutting a part of the metal plate along three sides of the rectangle, and are bent at the remaining one of the four sides of the rectangle so as to protrude toward one surface side of the metal plate. And, a hole is opened in the rectangular portion. Disclosure of Invention In addition to the high temperature of the exhaust gas to be treated, the exhaust gas purification apparatus may cause oxidation reaction or reduction reaction of pollutants in the exhaust gas, and thus may be heated to a high temperature by heat generation associated with the reaction. Further, if the device is mounted on a vehicle, the device may vibrate greatly due to the running of the vehicle. Since the exhaust gas purifying device is inevitably subjected to such thermal stress or external force, in the structure disclosed in, for example, japanese patent application laid-open No. 11-290699, the honeycomb structure is broken at the slit portion, and therefore the strength at this portion is weak, and as a result, the honeycomb structure is deformed or displaced by the thermal stress or vibration, and the honeycomb structures are in frictional contact with or collide with each other, and the honeycomb structure may be broken. On the other hand, in the exhaust gas purifying converter described in japanese patent application laid-open No. 2007-511699, exhaust gas is purified by making the exhaust gas flow laterally through a panel made of metal fibers supporting a catalyst, and bringing the exhaust gas into contact with the catalyst. However, since the panels are arranged in a direction parallel to the flow direction of the exhaust gas, it is desirable to disperse the exhaust gas over the entire surface of the panels, and for this purpose, a metal plate is arranged between the panels, and wing portions functioning as spacers are provided. That is, the metal plate in the exhaust gas purifying converter described in japanese patent laying-open No. 2007-511699 is a member for securing the interval between the panels, and does not particularly exert the function of purifying the exhaust gas. Therefore, in the exhaust gas purifying converter disclosed in japanese patent laying-open No. 2007-511699, the number of constituent parts increases, and therefore there is a possibility that the configuration as a whole of the apparatus increases. In particular, since the number of metal plates increases as the number of stacked pieces increases, the number of metal plates becomes a factor of increasing the weight, and there is a possibility of causing high cost. The present invention has been made in view of the above-described technical problems, and an object of the present invention is to provide an exhaust gas purifying